Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 57
Filtrar
1.
BMC Gastroenterol ; 23(1): 131, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081394

RESUMO

PURPOSE: Hepatocellular carcinoma (HCC) is a kind of primary liver cancer. It is a common malignant tumor of digestive system that is difficult to predict the prognosis of patients. As an important epigenetic modification, N7 methyl guanosine (m7G) is indispensable in gene regulation. This regulation may affect the development and occurrence of cancer. However, the prognosis of long non coding RNAs (lncRNAs) in HCC is limited, especially how m7G-related lncRNAs regulate the development of HCC has not been reported. METHODS: The Cancer Genome Atlas (TCGA) provides us with the expression data and corresponding clinical information of HCC patients we need. We used a series of statistical methods to screen four kinds of m7G-related lncRNAs related to HCC prognosis and through a series of verifications, the results were in line with our expectations. Finally, we also explored the IC50 difference and correlation analysis of various common chemotherapy drugs. RESULT: Our study identified four differentially expressed m7g-related lncRNAs associated with HCC prognosis. Survival curve analysis showed that high risk lncRNAs would lead to poor prognosis of HCC patients. M7G signature's AUC was 0.789, which shows that the prognosis model we studied has certain significance in predicting the prognosis of HCC patients. Moreover, our study found that different risk groups have different immune and tumor related pathways through gene set enrichment analysis. In addition, many immune cell functions are significantly different among different risk groups, such as T cell functions, including coordination of type I INF response and coordination of type II INF response. The expression of PDCD1, HHLA2, CTLA-4 and many other immune checkpoints in different risk groups is also different. Additionally, we analyzed the differences of IC50 and risk correlation of 15 chemotherapeutic drugs among different risk groups. CONCLUSION: A novel lncRNAs associated with m7G predicts the prognosis of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/genética , RNA Longo não Codificante/genética , Neoplasias Hepáticas/genética , Guanosina , Imunoglobulinas
2.
Mar Drugs ; 21(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37233487

RESUMO

Two new quinazolinone diketopiperazine alkaloids, including versicomide E (2) and cottoquinazoline H (4), together with ten known compounds (1, 3, and 5-12) were isolated and identified from Aspergillus versicolor AS-212, an endozoic fungus associated with the deep-sea coral Hemicorallium cf. imperiale, which was collected from the Magellan Seamounts. Their chemical structures were determined by an extensive interpretation of the spectroscopic and X-ray crystallographic data as well as specific rotation calculation, ECD calculation, and comparison of their ECD spectra. The absolute configurations of (-)-isoversicomide A (1) and cottoquinazoline A (3) were not assigned in the literature reports and were solved in the present work by single-crystal X-ray diffraction analysis. In the antibacterial assays, compound 3 exhibited antibacterial activity against aquatic pathogenic bacteria Aeromonas hydrophilia with an MIC value of 18.6 µM, while compounds 4 and 8 exhibited inhibitory effects against Vibrio harveyi and V. parahaemolyticus with MIC values ranging from 9.0 to 18.1 µM.


Assuntos
Alcaloides , Antozoários , Sesquiterpenos , Animais , Dicetopiperazinas/química , Estrutura Molecular , Fungos , Alcaloides/química , Antibacterianos/química
3.
Pharm Biol ; 61(1): 356-361, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36728978

RESUMO

CONTEXT: Poziotinib and vonoprazan are two drugs mainly metabolized by CYP3A4. However, the drug-drug interaction between them is unknown. OBJECTIVE: To study the interaction mechanism and pharmacokinetics of poziotinib on vonoprazan. MATERIALS AND METHODS: In vitro experiments were performed with rat liver microsomes (RLMs) and the contents of vonoprazan and its metabolite were then determined with UPLC-MS/MS after incubation of RLMs with vonoprazan and gradient concentrations of poziotinib. For the in vivo experiment, rats in the poziotinib treated group were given 5 mg/kg poziotinib by gavage once daily for 7 days, and the control group was only given 0.5% CMC-Na. On Day 8, tail venous blood was collected at different time points after the gavage administration of 10 mg/kg vonoprazan, and used for the quantification of vonoprazan and its metabolite. DAS and SPSS software were used for the pharmacokinetic and statistical analyses. RESULTS: In vitro experimental data indicated that poziotinib inhibited the metabolism of vonoprazan (IC50 = 10.6 µM) in a mixed model of noncompetitive and uncompetitive inhibition. The inhibitory constant Ki was 0.574 µM and the binding constant αKi was 2.77 µM. In vivo experiments revealed that the AUC(0-T) (15.05 vs. 90.95 µg/mL·h) and AUC(0-∞) (15.05 vs. 91.99 µg/mL·h) of vonoprazan increased significantly with poziotinib pretreatment. The MRT(0-∞) of vonoprazan increased from 2.29 to 5.51 h, while the CLz/F value decreased from 162.67 to 25.84 L/kg·h after pretreatment with poziotinib. CONCLUSIONS: Poziotinib could significantly inhibit the metabolism of vonoprazan and more care may be taken when co-administered in the clinic.


Assuntos
Microssomos Hepáticos , Espectrometria de Massas em Tandem , Ratos , Animais , Cromatografia Líquida , Interações Medicamentosas , Microssomos Hepáticos/metabolismo
4.
Environ Res ; 212(Pt C): 113408, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35561821

RESUMO

Understanding the roles of nutrient restriction in extracellular electron transfer (EET) and stability of mixed electroactive biofilm is essential in pollutant degradation and bioenergy production. However, the relevant studies are still limited so far. Herein, the effect of nutrient restriction on the EET pathways and stability of mixed electroactive biofilm was explored. It was found that the electroactive Pseudomonas and Geobacter genera were selectively enriched in the biofilms cultured under total nutrient and P-constrained conditions, and two EET pathways including direct and indirect were found, while Rhodopseudomonas genus was enriched in the N-constrained biofilm, which only had the direct EET pathway. Moreover, multiple analyses including 2D confocal Raman spectra revealed that P-constrained biofilm was rich in extracellular polymeric substances (EPS) especially for polysaccharide, presented a dense and uniform layered distribution, and had better stability than N-constrained biofilm with lower EPS and biofilm with heterostructures cultured under total nutrient conditions.


Assuntos
Biofilmes , Matriz Extracelular de Substâncias Poliméricas , Geobacter , Elétrons , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Geobacter/fisiologia
5.
Environ Res ; 211: 113006, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35227674

RESUMO

Microbial electrolysis cell (MEC) coupled anaerobic digestion (AD), named as MEC-AD system, can effectively promote methane production under ammonia inhibition, but the inherent mechanism is still poorly understood. This study comprehensively explored the MEC-AD performance and mechanism under high-concentration ammonia stress including using proteomic analysis. It was found that the methane generation rates in MEC-AD systems were 2.0-2.7 times that of AD ones under 5.0 g/L ammonia stress. Additionally, the experimental conditions for methane generation in MEC-AD systems were optimized using response surface methodology. Further analysis indicates that the activities of acetate kinase and F420 were improved, and particularly the direct interspecies electron transfer (DIET) was promoted in MEC-AD systems, as indicated by increased electroactive extracellular polymeric substance, decreased charge transfer resistance, and enrichment of electroactive microbes such as Geobacter on the bioelectrodes. Moreover, proteomic analysis reveals that the DIET associated proteins such as Cytochrome C was up-regulated, and ammonia transfer-related proteins were down-regulated and ammonium detoxification-related proteins were up-regulated in MEC-AD systems. This work provides us a better understanding on the MEC-AD performance especially for the treatment of wastewater containing high-concentration ammonia.


Assuntos
Amônia , Reatores Biológicos , Anaerobiose , Estimulação Elétrica , Matriz Extracelular de Substâncias Poliméricas , Metano , Proteômica
6.
Environ Res ; 210: 112897, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35151661

RESUMO

Chemical structure of azo dyes molecules showed significant influence on their decolorization rate, while the structure-activity relationship between chemical structure and their reduction decolorization rate is not fully understand. In this study, we found that azo dye molecule with closer position for electron-withdrawing substituent to azo bond resulted in faster chemical and biotic reduction rate with or without presence of carbon nanotubes (CNTs), while electron-repulsive substituent closer to azo bond leading to slower azo dye chemical and biotic reduction rate no matter with or without presence of CNTs. Additionally, galvanic cell experiments implied that electron transfer process may play important roles for both chemical and biological reduction decolorization of azo dyes, and CV results indicated that the higher (azo bond breakage) reduction wave potential corresponding to a faster azo dye chemical decolorization reaction. Finally, the results of Lowest Unoccupied Molecular Orbital (LUMO) energy established that lower LUMO energy for azo dye corresponding to a faster chemical decolorization reaction. This study not only offer systematized relationships between structure property of azo dye and their decolorization rate, but also provide a universal and propagable reduction rules.


Assuntos
Compostos Azo , Nanotubos de Carbono , Compostos Azo/química , Corantes/química , Elétrons , Relação Estrutura-Atividade
7.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36613800

RESUMO

Brassica napus is an important crop for edible oil, vegetables, biofuel, and animal food. It is also an ornamental crop for its various petal colors. Flavonoids are a group of secondary metabolites with antioxidant activities and medicinal values, and are important to plant pigmentation, disease resistance, and abiotic stress responses. The yellow seed coat, purple leaf and inflorescence, and colorful petals of B. napus have been bred for improved nutritional value, tourism and city ornamentation. The putative loci and genes regulating flavonoid biosynthesis in B. napus have been identified using germplasms with various seed, petal, leaf, and stem colors, or different flavonoid contents under stress conditions. This review introduces the advances of flavonoid profiling, biosynthesis, and regulation during development and stress responses of B. napus, and hopes to help with the breeding of B. napus with better quality, ornamental value, and stress resistances.


Assuntos
Brassica napus , Brassica napus/genética , Brassica napus/metabolismo , Melhoramento Vegetal , Flavonoides/metabolismo , Folhas de Planta/metabolismo , Sementes/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Sheng Li Xue Bao ; 74(6): 993-1004, 2022 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-36594387

RESUMO

A large number of ß-adrenergic receptor (ß-AR) agonists and antagonists are widely used in the treatment of cardiovascular diseases and other diseases. Nonetheless, it remains unclear whether these commonly used ß-AR drugs can activate downstream ß- arrestin-biased signaling pathways. The objective of this study was to investigate ß-arrestin2 recruitment effects of ß-AR agonists and antagonists that were commonly used in clinical practice. We used TANGO (transcriptional activation following arrestin translocation) assay to detect the ß-arrestin2 recruitment by ß-AR ligands in HEK293 cell line (HTLA cells) stably transfected with tetracycline transactivator protein (tTA) dependent luciferase reporter and ß-arrestin2-TEV fusion gene. Upon activation of ß-AR by a ß-AR ligand, ß-arrestin2 was recruited to the C terminus of the receptor, followed by cleavage of the G protein-coupled receptors (GPCRs) fusion protein at the TEV protease-cleavage site. The cleavage resulted in the release of tTA, which, after being transported to the nucleus, activated transcription of the luciferase reporter gene. The results showed that ß-AR non-selective agonists epinephrine, noradrenaline and isoprenaline all promoted ß-arrestin2 recruitment at ß1-AR and ß2-AR. ß1-AR selective agonists dobutamine and denopamine both promoted ß-arrestin2 recruitment at ß1-AR. ß2-AR selective agonists procaterol and salbutamol promoted ß-arrestin2 recruitment at ß2-AR. ß-AR non-selective antagonists alprenolol and pindolol promoted ß-arrestin2 recruitment at ß1-AR. ß1-AR selective antagonists celiprolol and bevantolol showed ß-arrestin2 recruitment at ß1-AR. ß2-AR selective antagonists butoxamine showed ß-arrestin2 recruitment at ß1-AR. These results provide some clues for the potential action of ß-AR drugs, and lay a foundation for the screening of ß-arrestin-biased ß-AR ligands.


Assuntos
Agonistas Adrenérgicos beta , Receptores Adrenérgicos beta 2 , Humanos , beta-Arrestina 2/genética , beta-Arrestina 2/metabolismo , Células HEK293 , Agonistas Adrenérgicos beta/farmacologia , Isoproterenol/farmacologia , Receptores Adrenérgicos beta 2/genética , Receptores Adrenérgicos beta 2/metabolismo , Norepinefrina/farmacologia
9.
Toxicol Mech Methods ; 31(5): 334-342, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33627030

RESUMO

Macrophages can polarize into different phenotypes in response to different microenvironmental stimuli. Macrophage polarization has been assigned to two extreme states, namely proinflammatory M1 and anti-inflammatory M2. Accumulating evidences have demonstrated that M1 polarized macrophages contribute to various toxicants-induced deleterious effects. Switching macrophages from proinflammatory M1 phenotype toward anti-inflammatory M2 phenotype could be a promising approach for treating various inflammatory diseases. Studies in the past few decades have revealed that nuclear factor erythroid 2-related factor 2 (Nrf2) can modulate the polarization of macrophages. Specifically, activation of Nrf2 could block M1 stimuli-induced production of proinflammatory cytokines and chemokines, and shift the polarization of macrophages toward M2 by cross-talking with nuclear factor kappa-B (NF-κB), mitogen-activated protein kinases (MAPKs), peroxisome proliferator-activated receptor γ (PPARγ), and autophagy. Importantly, a great number of studies have confirmed the beneficial effects of natural and synthesized Nrf2 agonists on various inflammatory diseases; however, most of these compounds are far away from clinical application due to lack of characterization and defects of study designs. Interestingly, some endogenous Nrf2 inducers and compounds with dual activities (such as the Nrf2 inducing and CO releasing effects) exhibit potent anti-inflammatory effects, which points out an important direction for future researches.


Assuntos
Macrófagos , Citocinas , Fator 2 Relacionado a NF-E2 , NF-kappa B , Xenobióticos/toxicidade
10.
J Biol Chem ; 294(38): 13915-13927, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31350334

RESUMO

Replication protein A (RPA) is the major eukaryotic ssDNA-binding protein and has essential roles in genome maintenance. RPA binds to ssDNA through multiple modes, and recent studies have suggested that the RPA-ssDNA interaction is dynamic. However, how RPA alternates between different binding modes and modifies ssDNA structures in this dynamic interaction remains unknown. Here, we used single-molecule FRET to systematically investigate the interaction between human RPA and ssDNA. We show that RPA can adopt different types of binding complexes with ssDNAs of different lengths, leading to the straightening or bending of the ssDNAs, depending on both the length and structure of the ssDNA substrate and the RPA concentration. Importantly, we noted that some of the complexes are highly dynamic, whereas others appear relatively static. On the basis of the above observations, we propose a model explaining how RPA dynamically engages with ssDNA. Of note, fluorescence anisotropy indicated that RPA can also associate with RNA but with a lower binding affinity than with ssDNA. At the single-molecule level, we observed that RPA is undergoing rapid and repetitive associations with and dissociation from the RNA. This study may provide new insights into the rich dynamics of RPA binding to ssDNA and RNA.


Assuntos
DNA de Cadeia Simples/metabolismo , RNA/química , Proteína de Replicação A/metabolismo , Cromatografia em Gel , DNA de Cadeia Simples/química , Polarização de Fluorescência/métodos , Transferência Ressonante de Energia de Fluorescência , Humanos , Ligação Proteica , RNA/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteína de Replicação A/química , Proteína de Replicação A/genética
11.
Int J Syst Evol Microbiol ; 70(6): 3740-3748, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32441611

RESUMO

A Gram-stain-negative, aerobic, gliding, rod-shaped (0.2-0.5×1.0-13.0 µm) and yellow-pigmented bacterium, designated PLHSN227T, was isolated from seawater collected near the coast of Yantai, PR China. PLHSN227T was found to grow at 15-37 °C (optimum, 28-30 °C) and pH 6.0-8.5 (optimum, 6.5-7.5) in the presence of 2-14 % (w/v) NaCl (optimum, 5.0 %). Phylogenetic analysis of the 16S rRNA gene sequences revealed that PLHSN227T represented a member of the family Flavobacteriaceae and exhibited the highest sequence similarity (94.6 %) to the type strain Salegentibacter holothuriorum NBRC 100249T. The chemotaxonomic analysis revealed that the sole respiratory quinone was menaquinone 6 (MK-6) and the major fatty acids included C19 : 0ω8c cyclo, iso-C15 : 0, anteiso-C15 : 0, C18 : 0 and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The major polar lipids included phosphatidylethanolamine, one unidentified aminolipid and two unidentified lipids. The DNA G+C content of PLHSN227T was 35.6 mol%. PLHSN227T showed the highest average amino acid identity value of 67.2 %, the average nucleotide identity value of 75.6 and 14.5 % digital DNA-DNA hybridization identity with Mesonia algae DSM 15361T. According to the phylogenetic data, PLHSN227T formed a distinct clade in the phylogenetic tree. On the basis of phenotypic, chemotaxonomic and phylogenetic data, it is considered that PLHSN227T represents a novel genus within the family Flavobacteriaceae, for which the name Haloflavibacter putidus gen. nov., sp. nov. is proposed. The type strain is PLHSN227T (=KCTC 72159T=MCCC 1H00371T).


Assuntos
Flavobacteriaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
J Biol Chem ; 293(48): 18504-18513, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30305390

RESUMO

G-quadruplexes (G4s) are four-stranded DNA structures formed by Hoogsteen base pairing between stacked sets of four guanines. Pif1 helicase plays critical roles in suppressing genomic instability in the yeast Saccharomyces cerevisiae by resolving G4s. However, the structural properties of G4s in S. cerevisiae and the substrate preference of Pif1 for different G4s remain unknown. Here, using CD spectroscopy and 83 G4 motifs from S. cerevisiae ranging in length from 30 to 60 nucleotides, we first show that G4 structures can be formed with a broad range of loop sizes in vitro and that a parallel conformation is favored. Using single-molecule FRET analysis, we then systematically addressed Pif1-mediated unwinding of various G4s and found that Pif1 is sensitive to G4 stability. Moreover, Pif1 preferentially unfolded antiparallel G4s rather than parallel G4s having similar stability. Furthermore, our results indicate that most G4 structures in S. cerevisiae sequences have long loops and can be efficiently unfolded by Pif1 because of their low stability. However, we also found that G4 structures with short loops can be barely unfolded. This study highlights the formidable capability of Pif1 to resolve the majority of G4s in S. cerevisiae sequences, narrows the fractions of G4s that may be challenging for genomic stability, and provides a framework for understanding the influence of different G4s on genomic stability via their processing by Pif1.


Assuntos
DNA Helicases/metabolismo , DNA Fúngico/química , DNA Fúngico/metabolismo , Quadruplex G , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Dicroísmo Circular , Transferência Ressonante de Energia de Fluorescência , Instabilidade Genômica , Ligação Proteica , Saccharomyces cerevisiae/genética , Temperatura
13.
J Cell Biochem ; 120(4): 5151-5159, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30324678

RESUMO

More and more evidence indicate long noncoding RNAs (lncRNAs) as competing endogenous RNAs (ceRNAs) to indirectly regulate messenger RNAs (mRNAs) by acting as microRNA (miRNA) sponges, which represents a novel layer of gene regulation that plays a critical role in the development of cancers. However, functional roles and regulatory mechanisms of lncRNA-mediated ceRNAs network in osteosarcoma are still largely unknown. Here, we comprehensively compared the expression profiles of mRNAs, lncRNAs, and miRNAs between osteosarcoma and normal samples from the Gene Expression Omnibus (GEO) to elaborate related latent mechanisms. Two lncRNAs, ie, LINC01560 and MEG3, were identified to be aberrantly expressed. Importantly, MEG3 was considered as a promising diagnostic biomarker and therapeutic target for patients with osteosarcoma according to the Kaplan-Meier analysis of another independent osteosarcoma data set from the Cancer Genome Atlas (P = 0.05). Eventually, we successfully established a dysregulated lncRNA-related ceRNA network, including one osteosarcoma-specific lncRNA, three miRNAs and four mRNAs. In conclusion, this study should be beneficial for improving our understanding of the lncRNA-mediated ceRNA regulatory mechanisms in the pathogenesis of osteosarcoma and providing it with novel candidate diagnostic and therapeutic biomarkers.


Assuntos
Carcinogênese/patologia , MicroRNAs/metabolismo , Osteossarcoma/genética , Osteossarcoma/patologia , RNA Longo não Codificante/metabolismo , Carcinogênese/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Environ Sci Technol ; 53(8): 4397-4405, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30908036

RESUMO

Pyrogenic carbonaceous matter (PCM) catalyzes the transformation of a range of organic pollutants by sulfide in water; however, the mediation mechanisms are not fully understood. In this study, we observed for the first time that the degradation of azo dyes by sulfide initially underwent a lag phase followed by a fast degradation phase. Interestingly, the presence of PCM only reduced the lag phase length of the azo dye decolorization but did not significantly enhance the reaction rate in the fast degradation phase. An analysis of the azo dye reduction and polysulfide formation indicated that PCM facilitated the transformation of sulfide into polysulfides, including disulfide and trisulfide, resulting in fast azo dye reduction. Moreover, the oxygen functional groups of the PCM, especially the quinones, may play an important role in the transformation of sulfide into polysulfides by accelerating the electron transfer. The results of this study provide a better understanding of the PCM-mediated abiotic transformation of organic pollutants by sulfide in anaerobic aqueous environments.


Assuntos
Compostos Azo , Sulfetos , Corantes , Transporte de Elétrons , Oxirredução , Quinonas
15.
Environ Sci Technol ; 53(12): 6927-6936, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31117534

RESUMO

Promotion of iron solubility using ligands is the preliminary step in the homogeneous electro-Fenton (EF) process at a mild pH, but the chelate efficiencies of most organic ligands are unsatisfactory, resulting in insufficient Fe(II) availability. In this study, atomic H* was, for the first time, introduced to the EF process to accelerate the regeneration of the Fe(II)-complex at a mild pH using a Ni-deposited carbon felt (Ni-CF) cathode. The introduction of atomic H* significantly elevated total organic carbon (TOC) abatement of ciprofloxacin (CIP) from 42% (CF) to 81% (Ni-CF) at a natural pH. In the presence of humic acids (HAs), atomic H* introduced via Ni-CF enhanced the CIP degradation rate to 10 times that of the CF at a mild pH. The electron spin resonance (ESR), density functional theory (DFT) calculations, electrochemical characterization, and in situ electrochemical Raman study clearly demonstrated that the atomic H* generated from the Ni-CF cathode was highly efficient at reducing Fe(III)-complexes at a natural pH. Additionally, the Ni-CF could generate atomic H* without significant nickel leaching. Thus, the atomic H* could continuously facilitate iron cycling and, consequently, enhance pollutant mineralization via the homogeneous EF process at a mild pH in an environmentally friendly manner.


Assuntos
Compostos Ferrosos , Poluentes Químicos da Água , Eletrodos , Compostos Férricos , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Oxirredução
16.
Biochem Biophys Res Commun ; 499(1): 8-16, 2018 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-29534962

RESUMO

Gastric cancer is the third leading cause of cancer-associated death worldwide. Although a decrease in its incidence is observed, gastric cancer still poses a major clinical challenge due to poor prognosis and limited treatments. Barbaloin (BBL) is a main medicinal composition of the Chinese traditional medicine aloe vera. BBL has various bioactivities, including anti-oxidant, anti-inflammatory and anti-tumor properties. Polydopamine (pD)-based surface modification is easy to functionalize polymeric nanoparticles (NPs) surfaces with ligands and/or additional polymeric layers. In the present study, BBL-loaded formulations was developed with pD-modified NPs, which was synthesized by polylactide-TPGS (PLA-TPGS) (pD-PLA-TPGS/NPs). And galactosamine (Gal) was conjugated on the prepared NPs (Gal-pD-PLA-TPGS/NPs) for targeting the gastric cancer cells. Here, we found that BBL-loaded Gal-pD-PLA-TPGS/NPs showed the highest cellular uptake efficacy in gastric cancer cells. Gal-pD-PLA-TPGS/NPs more significantly reduced the gastric cancer cell viability. Further, greater apoptosis, autophagy and ROS generation was induced by Gal-pD-PLA-TPGS/NPs in gastric cancer cells. Additionally, compared to the other two NPs, Gal-pD-PLA-TPGS/NPs most markedly decreased ATP levels in gastric cancer cells. In vivo, Gal-pD-PLA-TPGS/NPs were specifically targeted to tumor site. Moreover, Gal-pD-PLA-TPGS/NPs exhibited the most anti-tumor effects, as evidenced by the lowest tumor volume and tumor weight. Of note, there was no significant difference was observed in body and liver weight, as well as the histological changes in major organs isolated from each group of mice. Together, the findings indicated that BBL-loaded Gal-pD-PLA-TPGS/NPs could be targeted to gastric cancer cells to suppress tumor progression without toxicity.


Assuntos
Antracenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Sistemas de Liberação de Medicamentos , Células Epiteliais/efeitos dos fármacos , Nanopartículas/química , Neoplasias Gástricas/tratamento farmacológico , Animais , Antracenos/química , Antineoplásicos Fitogênicos/química , Transporte Biológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Composição de Medicamentos/métodos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Galactosamina/química , Galactosamina/metabolismo , Humanos , Indóis/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/administração & dosagem , Poliésteres/química , Polímeros/química , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Vitamina E/química , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Appl Opt ; 55(20): 5341-4, 2016 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-27409308

RESUMO

A laser diode array (LDA) end-pumped continuous-wave single-frequency Innoslab amplifier has been demonstrated. The Gaussian ray bundle method was used to model the light propagation in the Innoslab amplifier for the first time to the best of our knowledge. With discrete reflectors, the maximum output of 60 W with a linewidth of 44 MHz was achieved under the pump power of 245 W, corresponding to the optical-optical efficiency of 24.5%. The beam quality factor M2 at the output power of 51 W in the horizontal and vertical direction was measured to be 1.4 and 1.3, respectively. The long-term power instability in 2 h was less than 0.25%.

18.
Appl Opt ; 54(23): 7120-3, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26368385

RESUMO

In this study, we experimentally demonstrate the generation of 760 fs pulse duration from a diode-pumped Yb:LuAG mode-locked laser at 1032 nm. At the repetition rate of 58.6 MHz, the maximum average power of 1.07 W was obtained, corresponding to the peak power of 24 kW. To our knowledge, these results represent the shortest pulse duration and highest peak power ever obtained for a 1032 nm mode-locked laser with Yb:LuAG crystal.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(12): 3218-23, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25881412

RESUMO

The authors have investigated the optical properties of core-shell structure of mist wrapped dust particles based on the method of discrete dipole approximation (DDA). The influence on the thickness of the elliptical core-shell structure were calculated which the ratio of long axis and short axis is 2:1, and the change of scattering angle for scattering characteristics. The results shows that the thickness of outer layer increase from 1.2 to 4.8 µm with the scattering and extinction coefficient of double core-shell layers particles decrease from 3.4 and 3.43 to 2.543 and 2.545, when the size of inner core isn't change. And scattering relative strength also increased obviously. The thickness of inner core increase from 0.6 to 2.4 µm with the of scattering and extinction coefficient change from 2.59 and 2.88 to 2.6 and 2.76 when thickness of outer remain constant. Effect of the thickness of visible outer layer on the scattering characteristics of double core-shell layers particles is greater, because of the interaction between scattering light and outer materials. The scattering relative intensity decrease with wavelength increased, while increased with the scale of core-shell structure increase. The results make a promotion on the study of the transportation characteristics of laser and scattering characteristics when the atmospheric aerosol and water mist interact together.

20.
Phytochemistry ; 220: 114000, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38278465

RESUMO

Sumalarins D-G (1-4), four previously undescribed curvularin derivatives, along with two known related metabolites, curvularin (5) and dehydrocurvularin (6), were isolated and identified from the mangrove-derived fungus Penicillium sumatrense MA-325. Among them, sumalarin D (1) represents a unique example of curvularin derivative featuring a 5-methylfuran-2-yl-methyl group. Their structures were elucidated based on analysis of NMR and MS data as well as comparison of ECD spectra and quantum chemical calculations of NMR, and compound 1 was confirmed by X-ray crystallographic analysis. Compounds 1, 2, 5, and 6 are active against aquatic pathogenic bacteria Vibrio alginolyticus and V. harveyi with MIC values ranging from 4 to 64 µg/mL, while compound 6 is cytotoxic against tumor cell lines 5673, HCT 116, 786-O, and Hela with IC50 values of 3.5, 10.6, 10.9, and 14.9 µM, respectively.


Assuntos
Antineoplásicos , Penicillium , Zearalenona/análogos & derivados , Estrutura Molecular , Penicillium/química , Antineoplásicos/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA